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The Journal of China Universities of posts and telecommunications 2003年第4期10卷 33-38,58页

作者： ZHANG Jian-hua,ZHANG Ping(Wireless Innovation Technologies Laboratory (WTI Lab), beijing university of posts and telecommunications, beijing 100876, P.R. China) Wireless Innovation Technologies Laboratory (WTI Lab) Beijing University of Posts iincl Telecommunications 北京 100087

In this paper the Inter-Channel-Interference (ICI) caused by Doppler spread is analyzed in the discrete form for an Orthogonal Frequency Division Multiplexing (OFDM) system. By theoretic derivation it is verified that the ICI power of the flat channel is the same as that of the time dispersive channel with the assumption that the flat channel is a normalized Wide-Sense Stationary (WSS) stochastic process and the time dispersive channel is a normalized Wide-Sense Stationary and Uncorrelatd-Scatting (WSS-US) stochastic process. Furthermore, the analysis and simulation show that the ICI power is determined by the product of Doppler spread and OFDM symbol period.

关键词： OFDM Time-Varying Channel(TVC) ICI

A New Anti-Collision Algorithm for Multi-Target Real Time Recognitionin RFID System

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The Journal of China Universities of posts and telecommunications 2000年第3期7卷 64-69页

作者： SHEN Yu chao, WANG Hai bo, SHEN Shu qun, XU Da xiong (school of Electronic Engineering,beijing university of{3. and telecommunications,beijing 100876,P.R.China) school of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 P. R. China

The problem of how to distinguish and recognize more than one target when they are entering the working area of the Radio Frequency Identification( RFID ) system should be considered in design of the system. To avoid signal interference with each other among all targets, an anti collision algorithm as well as the condition of working stability is proposed. The computer simulation shows that the new algorithm will be of advantages in the process of system design.

关键词： radio frequency radio frequency identification antenna anti collision algorithm

A Simple Capacity Formula for Correlated Diversity Rayleigh Fading Channels

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The Journal of China Universities of posts and telecommunications 2004年第Z1期11卷 37-39页

作者： CHENG Xing-qing~1, SU Shu-chun~2, LI Dao-ben~1 1.beijing university of posts and{3.,beijing 100876, P.R. China 2.beijing Electronic science Technology Institute,beijing 100070, P.R. China beijing university of posts and{3. Beijing 100876 P.R. China beijing Electronic science Technology Institute Beijing 100070 P.R. China

The system capacity can be considerably increased if we appropriately exploit the randomness of multipath propagation. A simple average capacity formula is derived for correlated diversity Rayleigh fading channels through linear transformation method. Numerical results that illustrate the effect of correlation parameter and diversity order on the diversity capacity are also presented.

关键词： channel capacity fading channel and wireless SIMO systems

An Analysis of Near Field and Application of a New Comb-shaped Antenna for Radio Frequency Identification

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The Journal of China Universities of posts and telecommunications 2001年第2期8卷 40-44页

作者： YU Xing qi, SHEN Shu qun, JIANG Chun bo, ZHAO Ji jun (school of Electroicn Engineering, beijing university of posts and telecommunications, beijing 100876,P.R.China) school of Electroicn Engineering Beijing University of Posts and Telecommunications

A new comb shaped antenna for radio frequency identification is proposed. The kind of antenna can replace some antenna array. So it is very convenient for omnidirectional identification. The test result proves this a... 详细信息

关键词： radio frequency identification antenna electromagnetic field

REAL SEQUENCES WITH GOOD AUTO-CORRELATION AND CROSS-CORRELATION

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Journal of Electronics(China) 1991年第1期8卷 68-76页

作者：杨义先 beijing university of posts and{3. Beijing

New classes of real sequences with good auto-correlation and cross-correlation areconstructed by using sinusoidal functions. The new sequences are better than the FZC and Alltopsequences in two aspects: (1) lower corr... 详细信息

关键词： Communication theory Correlation functions Sequences

Home Network and Digital Rights Management Technology

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ZTE Communications 2006年第4期4卷 12-18页

作者： Yang Cheng 1Wang Yongbin 2Yang Yixian 3.1. Information Engineering school, Communication university of China, beijing 100024, China 2. Computer and Software school, Communication university of China, beijing 100024, China 3. Information Security Center, beijing university of posts and telecommunications, beijing 100876, China) China China China

The home network is a major concern for the growth of digital and information society. Yet, how to guarantee the security of its digital content and protect the legal benefits for each section of the value chain becomes a crucial "bottleneck" in the home network development. The Digital Rights Management (DRM) technology provides total solution for usage, storage, transfer, and tracing the digital contents and rights. Its basic features are systematic and controllability. Considering the growth of the new media and services and the requirements of the Intellectual Property Rights (IPR) protection in a home network, it's necessary to solve consistency problems in usage, storage, and transfer of contents and rights. In addition, it is inevitable to conduct researches of key techniques such as end-to-end secure transmission, conditional access and play, and right description.

关键词： HDCP Home Network and Digital Rights Management Technology ZTE ISDB ATSC

AN IDENTITY-BASED PERSONAL LOCATION SYSTEM WITH PROTECTED PRIVACY IN IOT

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AN IDENTITY-BASED PERSONAL LOCATION SYSTEM WITH PROTECTED PR...

Conditions of the Classical Transmission Line Equations at High Frequency

2011 4th IEEE International Conference on Broadband Network and Multimedia Technology

作者： Chunye Hu 1 Jie Zhang 1 Qiaoyan Wen 2 1 school of science beijing{3. of posts and telecommunications beijing 100876 China 2 State Key Laboratory of Networking and Switching Technology beijing{3. of posts and telecommunications beijing 100876 China

The internet of things（IOT）has the same security requirements as traditional network,but according to the characteristics of its own,the internet of things also has some specific security features. Among these features,the flexibility of the network requires nodes to apply corresponding measures when scene *** example,in emergency situations（*** accident occurs,and a doctor is needed）,the location of the user is available,while under normal circumstances,the user’s location information is *** paper is in the background of the above scene to present an identity based system for personal location in emergency *** proposed system consists of registration subsystem,user authentication subsystem,policy subsystem and client *** system confirms the identity of the user through the user authentication subsystem and gets the level of the emergency through the policy *** it can make sure that user’s location information can be accessed only by some authorized user,and only when *** proposed system strengthens the protection of the user’s privacy while providing the location of the user,and prevents the disclosure of the users’information.

关键词： emergency situations virtual identity internet of things(IOT) privacy security

来源： cnki会议评论

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The Journal of China Universities of posts and telecommunications 2000年第Z1期 41-45页

作者： HE Wei1, GAO You-gang2 (1 school of Physics and Telecommunication, Yunnan Normal university, Kunming 650092, P.R.China 2.school of Telecommunication Engineering,{3., beijing 100876, P. R.

New transmission line equations are deduced applying Maxwell’s equations in this paper. The conditions of the classical transmission line equations have been discussed, which is important to solve the EM problems in ... 详细信息

关键词： transmission line high frequency double-wire system EM coupling

AN EFFICIENT MOTION ESTIMATION ALGORITHM FOR H.264/AVC H.264/AVC

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AN EFFICIENT MOTION ESTIMATION ALGORITHM FOR H.264/AVC H.264...